Answer: y = 15
Step-by-step explanation:
6y - 10 + 6y + 10 = 180
+ 10 - 10 -10 +10
12y = 180
12y/12 = 180/12
y = 15
1. 5 2. 7 3. 6 simply add the images together to get your answer. I hope that helps
We will start off working on the right hand side.
<span>cot x - tan x </span>
<span>= [cos x / sin x] - [sin x / cos x] </span>
<span>= [(cos x)^ 2 - (sin x)^2] / [sin x cos x] </span>
<span>This is where it gets a bit tougher if you do not have your formula list with you. </span>
<span>(cos x)^ 2 - (sin x)^2 = cos(2x) </span>
<span>sin 2x = 2 sin x cos x </span>
<span>Note that by arranging the second formula, we will have sin x cos x = (1/2) sin 2x </span>
<span>Hence, we will get: </span>
<span>[(cos x)^ 2 - (sin x)^2] / [sin x cos x] </span>
<span>= [cos 2x] / (1/2)[sin 2x] </span>
<span>= 2[cos 2x] / [sin 2x] </span>
<span>= 2cot 2x </span>
90% out of 105% which would be 0.85
